An experimental result showed that ECT2 can act as GEF to mediate the transformation and growth of tumor cells by activating Rac in the nucleus and RhoA in the cytoplasm; In cells, nuclear-localized ECT2 and its Rho GEF activity can promote the growth and transformation of ovarian cancer cells; However, cytoplasmically localized ECT2 does not promote the transformation of cancer cells, but may counteract its role in the nucleus (Haverty et al., 2009). The gene discussed is RHOA; the disease is cancer.